GilbertThompson_CivilWar

On November 22, 1864, as Grant was tightening the noose around Petersburg, Thompson became an assistant engineer with the Army of the Potomac’s Headquarters near City Point. Several days later, a talented young war photographer, Timothy O’Sullivan, turned up with his traveling darkroom, making pictures about the huts and tents. One group he photographed was composed of the small Headquarters staff of draughtsmen and engineers—and that is quite likely Thompson sitting in their midst.